Place value

problem

Phew I'm Factored

Age

14 to 16

Challenge level

Explore the factors of the numbers which are written as 10101 in different number bases. Prove that the numbers 10201, 11011 and 10101 are composite in any base.
problem

BT... Eat Your Heart Out

Age

16 to 18

Challenge level

If the last four digits of my phone number are placed in front of the remaining three you get one more than twice my number! What is it?
problem

Binary Squares

Age

16 to 18

Challenge level

If a number N is expressed in binary by using only 'ones,' what can you say about its square (in binary)?
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Learn About Number Bases

We are used to writing numbers in base ten, using 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. Eg. 75 means 7 tens and five units. This article explains how numbers can be written in any number base.
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An Alphanumeric

Freddie Manners, of Packwood Haugh School in Shropshire solved an alphanumeric without using the extra information supplied and this article explains his reasoning.
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Number Sense Series: A Sense of 'ten' and Place Value

Once a basic number sense has developed for numbers up to ten, a strong 'sense of ten' needs to be developed as a foundation for both place value and mental calculations.
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Palindromes

Find out about palindromic numbers by reading this article.
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Adding With the Abacus

Nowadays the calculator is very familiar to many of us. What did people do to save time working out more difficult problems before the calculator existed?
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Pupils' Recording or Pupils Recording

This article, written for teachers, looks at the different kinds of recordings encountered in Primary Mathematics lessons and the importance of not jumping to conclusions!
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Ten-Frames Games

These games use ten-frames to develop children's 'sense of ten'.